Answer:
10. B
13. It's actually 30 seconds but 20 comes closest so B
14. B, any type of stretching is good before you perform any type of physical activity because it loosens up the muscles
15. D, all of the above
Explanation:
I have done many sports in my life and am still very active, I grew to know most of these things through the years.
Answer:
HERE IS YOUR ANSWER
Explanation:
1. The machines makes pur life easier.
2. It makes us do our works faster.
3. It does all the works that are harder for us.
Hope it helps you.
Answer:
Explanation:
Arrangements of cells, when two or more cells are connected together they form what is called a battery
There are two ways cells can be connected
1. Parallel
2. Series
Find attached a sketch of serial arrangement
Answer:
The force on q₁ due to q₂ is (0.00973i + 0.02798j) N
Explanation:
F₂₁ = 
Where;
F₂₁ is the vector force on q₁ due to q₂
K is the coulomb's constant = 8.99 X 10⁹ Nm²/C²
r₂₁ is the unit vector
|r₂₁| is the magnitude of the unit vector
|q₁| is the absolute charge on point charge one
|q₂| is the absolute charge on point charge two
r₂₁ = [(9-5)i +(7.4-(-4))j] = (4i + 11.5j)
|r₂₁| = 
(|r₂₁|)² = 148.25

= 0.050938(0.19107i + 0.54933j) N
= (0.00973i + 0.02798j) N
Therefore, the force on q₁ due to q₂ is (0.00973i + 0.02798j) N
Explanation:
see the above attachment to solve the question and get the answer.
hope this helps you.