The powerhouse of the cell: that is a term used to describe the because it's main function is to produce energy for cellular activities.
a) nucleus
b) mitochondria
c) golgi bodies
d) endoplasmic reticulum

Mitochondria

Explanation:

The power house of the cell is known as Mitochondria. The energy that is required by the body is provided by mitochondria.

The hydrolysis of the ATP takes place in which it is converted into ADP and Pi and some amount of energy is released.

This energy is used by the body for the various types of metabolic activities. The site of ATP formation is mitochondria.

oceans

indian ocean

pacific ocean

atlantic ocean

arctic ocean

southern ocean

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.