Using the mirror formula.
1/v + 1/u = 1/f
1/9.5 + 1/3.2 = 1/f
1/f = 3.2 + 9.5 / 9.5 * 3.2
1/f = 4.82 cm
Radius = 2f
Radius = 2 x 4.82
Radius = 9.64 cm
Each electron has a charge of

In this problem, the total charge is

Therefore, the number of electrons contained in this total charge will be given by the total charge divided by the charge of a single electron:

Calcium chloride contains ionic bonds.
Pennies contain metallic bonds.
Hydrochloric acid contains covalent bonds.
You're welcome.
Hypothesis testing is basically testing the results of a experiment to see weather your results are valid or not.
Looks like you simply substitute the length of the femur