What does the strength of friction depend on?
A. The direction of the forces.
B. The types of surfaces and how hard the
mbjects are being pushed.
C. The color of surfaces and how hard they push.
D. Only how hard the objects are being pushed.

the direction of force.

good one: produce hormones that plants grow.

bad one: the problem with organic matter is that while plant nutrients are needed for crop growth, they can also stimulate excessive growth of the wrong plants – mainly, algae.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus. this is so because calcium carbonate is the main component in the shells.

explanation: