Pls !

which of the following agricultural practices can lead to algal blooms? select the two correct answers.
- sediments released by tilling of soil
- withdrawls of water for crop irrigation
- animal waste accumulated in livestock production
- application of nutrients to crops
- erosion caused by livestock overgrazing

The agricultural practices can lead to algal blooms are:

Animal waste accumulated in livestock production Application of nutrients to crops  

Explanation:

Unsustainable agricultural practices and livestock production leads to an algal bloom. Algal blooms are mainly caused due to eutrophication of water bodies like lakes, rivers, streams, ponds, seas etc with an increase of nutrients like phosphorous and nitrogen.

Nutrients like phosphorus and nitrogen are present in large amounts in fertilizers (NPK fertilizers) or manure applied to the crops, excess of which settles on the ground.

Animal wastes contain ammonia and other nitrogenous compounds. Improper waste management in livestock production leads to the accumulation of these wastes.

When it rains, these soil nutrients and accumulated animal wastes runoff and get carried and washed away by the flowing water and reach these water bodies. The water bodies get highly enriched with these nutrients which lead to eutrophication and algal blooms.

The answer is c. they had seedshope this

Mantle convection  is the slow  creepingmotion of earth's solid silicate  mantle  caused by  convection  currents carrying  heat from the interior  to the planet's surface.[1][2]  the earth's surface  lithosphere, which rides atop the  asthenosphere  (the two components of the  upper mantle), is divided into a number of  plates  that are continuously being created and consumed at their opposite  plate boundaries. accretion occurs as mantle is added to the growing edges of a plate, associated with  seafloor spreading. this hot added material cools down by  conduction  and  convection  of heat. at the consumption edges of the plate, the material has thermally contracted to become dense, and it sinks under its own weight in the process of  subduction  usually at an  ocean trench.[3]this subducted material sinks through the earth's interior. some subducted material appears to reach the lower mantle,[4]  while in other regions, this material is impeded from sinking further, possibly due to a phase transition from  spinel  to  silicate perovskiteand  magnesiowustite, an  endothermic reaction.[5]the subducted oceanic crust triggers  volcanism, although the basic mechanisms are varied. volcanism may occur due to processes that add buoyancy to partially melted mantle causing an upward flow due to a decrease in density of the partial melt.secondary forms of convection that may result in surface volcanism are postulated to occur as a consequence of intraplate extension[6]  and  mantle plumes.[7]it is because the mantle can convect that the  tectonic plates  are able to move around the earth's surface.[8]mantle convection seems to have been much more active during the  hadean  period, resulting in gravitational sorting of heavier molten  iron, and  nickel  elements and  sulphides  in the core, and lighter  silicate minerals  in the  mantle.