Answer:
33 yrs old 
Step-by-step explanation:count up to the year he was born
 
        
             
        
        
        
5*4^2-3*4*5=80-60=20
Hope that helps you
        
             
        
        
        
Answer:
C = 87.92 mm
General Formulas and Concepts:
<u>Symbols</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Geometry</u>
Circumference Formula: C = πd
- <em>C</em> is circumference
- <em>d</em> is diameter
Step-by-step explanation:
<u>Step 1: Define</u>
Diameter <em>d</em> = 28 mm
<u>Step 2: Solve</u>
- Substitute in variables [Circumference Formula]:                                          C = 3.14(28 mm)
- [Circumference] Multiply:                                                                                 C = 87.92 mm
 
        
             
        
        
        
Use trigonometry.
tan30° = perpendicular / base
Here for angle 30° , x is perpendicular while 10 is the base.
tan30° = 1/√3
1/√3 = x/10
 x = 10/✓3
By rationalising 
x = 10√3/3
Hope This Helps You!
        
             
        
        
        
Use proportion, so multiply 100 by 75, then divide it by 30 and that's your answer.....250