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# Question: i need assistance with these10andnbspandnbspa boy walks 155 m at...

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i need assistance with these

10.  A boy walks 155 m at a speed of 3.5 m/s and then runs for 100 m at 8.2 m/s along a straight line. Calculate his average velocity.

(a) 3.0 m/s

(b) 4.5 m/s

(c) 4.0 m/s

(d) 2.5 m/s

(e) 1.0 m/s

(f)  12.0 m/s

11.  A boat can accelerate from 2 to 21 km/h in 10 s. How far has the boat travelled in this time ?

(a) 32 m

(b) 30 m

(c) 12 m

(d) 25 m

(e) 35 m

(f)  22.5 m

12.  A Porsche travelling at a constant velocity of 32 m/s passes a Mini parked on the side of the road. When the Porsche is 50 m ahead, the Mini starts accelerating uniformly at 3.5 m/s2. How fast is the Mini travelling when it reaches the Porsche ?.

(a) 36 m/s

(b) 45 m/s

(c) 12 m/s

(d) 69 m/s

(e) 78 m/s

(f)  112 m/s

13.  Three vectors are given by A = 3iB = -1i +1j and C = 4j. Find the magnitude of the resultant vector.

(a) 6.3

(b) 5.4

(c) 5.0

(d) 2.3

(e) 1.1

(f)  0.5