<h2>
ANSWER:</h2>
D.No, she is not accelerating because her speed is constant.
<h2>
EXPLANATION:</h2>
The rate of change of velocity with respect to time is known as acceleration.
acceleration =change in velocity/time
As she is running at constant speed and there is no change in velocity so she is not accelerating.
The relative molecular mass of acid A : 50 g/mol
<h3>Further explanation</h3>
Given
40.0 cm³(40 ml) of 0.2M sodium hydroxide
0.2g of a dibasic acid
Required
the relative molecular mass of acid A
Solution
Titration formula
M₁V₁n₁=M₂V₂n₂
n=acid/base valence(number of H⁺/OH⁻)
NaOH ⇒ n = 1
Dibasic acid = diprotic acid (such as H₂SO₄)⇒ n = 2
mol = M x V
Input the value in the formula :(1 = NaOH, 2=dibasic acid)
0.2 x 40 x 1 = M₂ x V₂ x 2
M₂ x V₂ = 4 mlmol = 4.10⁻³ mol ⇒ mol of Acid A
The relative molecular mass of acid A (M) :

The ABC fire extinguisher.
It looks like part of the Periodic Table. Do you have to write down the most common Periodic Table elements? If so, then that's probably what you should do.