I'm pretty sure 10/63 is simplified.
Answer:
Option 2: 
Step-by-step explanation:
Given:
From the triangle shown below;
A triangle QRS with angle QRS = 90°, ∠QSR = 30°.
Side QR = 5, SQ = 10 and RS = 5√3
Now, we know from trigonometric ratio that,

Here, opposite side of angle QSR is QR and Hypotenuse is the side opposite angle QRS which is SQ. Therefore,

Therefore, the value of sine of 30° is one-half. So, second option is correct.
Question:

There are two methods of doing this. One is via long division. It is long, and hard to type in a meaningful way, so I will not include that method. The other, which I often employ for dividing by small amounts such as 4, is to divide it in half 2 times. This is possible because 4 = 2 times 2. You now have the fractions

Therefore the solution is 90.
<h3>
Answer: 3 m/s^2</h3>
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According to Newton's Second Law, we know that
F = m*a
where F is the force applied, m is the mass and 'a' is the acceleration.
We see that this is a direct variation equation for F and a, such that m is the constant of variation. It's similar to how y = kx is also a direct variation equation.
Plug in F = 35 and a = 5 to find m
F = ma
35 = m*5
35/5 = m
7 = m
m = 7
The object has a mass of 7 kg
Our equation F = ma updates to F = 7a
Now plug in the force F = 21 to find 'a'
F = 7a
21 = 7a
21/7 = a
3 = a
a = 3
The acceleration will be 3 m/s^2
Notice how a smaller force applied means that the acceleration has also gone down as well.