Can someone help with number 4 please

The way I look at these things is like this:

-- The runner covered 12 meters in 4 seconds.
Average speed = 3 meters per second.

-- Speed at the beginning = zero.
In order to make the average 3, Speed at the end = 6 meters per second.

-- Speed increased from zero to 6 meters per second in 4 seconds.
It must have increased 1.5 meters per second each second.

That's choice-#2.

Here we have - 
Acceleration (a) = ?
Initial velocity (u) = 0 m/s (runner starts from rest)
Distance (s) = 12 m
Time (t) = 4 seconds

So, using the second equation of motion, we have-











So, option (2) is correct.

Ifound this on google “the middle ear contains three tiny bones known as the ossicles: malleus, incus, and stapes. the ossicles were given their latin names for their distinctive shapes; they are also referred to as the hammer, anvil, and stirrup, respectively.” i hope this you for what your looking for

The charge of an ion with 55 protons and 52 electrons is +3. the reason is because protons are positive, and there are three more than the amount of negative electrons.