Need with part b. is part a 140 times?

1680, and No

Step-by-step explanation:

Part A: A mockingbird beats its wings 420 times per 30 seconds (half a minute). This means that a mockingbird will beat its wings 840 times per minute. Multiply this by two and you get 1680 times in two minutes.

Part B: Divide the amount of beats in a minute by 60 (because there are 60 seconds in a minute) and you get the amount of times a mockingbird beats it wings per second.

420/30 = 14 times per second

Ariel said it was 0.07 times per second which is incorrect.

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

step-by-step explanation:

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