Gregory wants to make a hole in a flat piece of wood. He places object Y on the piece of wood, and then object X on top of it.

He then pushes down while rotating object X. Which two simple machines is Gregory using to perform this task?
A.
a wheel and axle and a pulley
B.
a pulley and an inclined plane
C.
a screw and a wedge
D.
a wheel and axle and a screw

Gregory wants to make a hole in a flat piece of wood. He places object Y on the piece of wood, and then object X on top of it.(C) a screw and a wedge

Explanation:

Screw is used to drill a hole in the wood and the wedge is used to insert it properly.

The screw moves in a circular motion and thus creates a hole in the wood whereas a wedge is used to apply appropriate force on the screw .so that it can be placed properly in the wood.

The a screw and a wedge are termed as simple machines.Simple machines are those machines that we make use of to do day to day task at home.

So we can say that Gregory wants to make a hole in a flat piece of wood. He places object Y on the piece of wood, and then object X on top of it.(C) a screw and a wedge

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.