URGENT!!! PLEASE HELP Europium has two naturally-occurring isotopes: europium-151 with an abundance of 47.82% and europium-153 with an abundance of 52.18%. Determine the average atomic mass for europium.

Urea, co(nh2)2, is manufactured on a large scale for use in producing urea-formaldehyde plastics and as a fertilizer. what is the maximum mass of urea that can be manufactured from the co2 produced by combustion of 1.00 x 104 grams of co2?

The missing component to the table to the right or indicated with orange letters complete the table by filling in the corresponding numbers or symbols

Ariver current has a velocity of 5km/h relative to the shore, and a boat moves in the same direction as the current at 5 km/h relative to the river. how can the velocity of the boat relative to the shore be calculated?