Can any one help me i really need it

The circumference is approximately 125.66.

Step-by-step explanation:

The formula for circumference is 2 x 3.14(r). Radius (or r) in this case is equal to 20 since the diameter is two times the length of the radius. 40/2 = 20.

2 x 3.14(20) ≈ 125.66

10

step-by-step explanation:

7+3=10

intensity of the vector is v= √37 ≈ 6.08 units and make angle ∡α ≈ 9.46° with east direction

step-by-step explanation:

required vector is consists of the two componentsvx= 2+4=6 units   and vy= 1 unit and vx ⊥ vywe will use pythagorian theorem to find intensity of the vector vv∧2 = vx∧2 + vy∧2 => v = √vx∧2 + vy∧2 = √6∧2 + 1∧2 = √36+1 = √37 ≈ 6.08 unitsthe angle ∡α between vector and east direction we wil find with tanαtanα = 1/6 => α = arc tanα = arc 1/6 => α ≈ 9.46°

hope this