1. andrew ran a marathon in about 1.56 x 10^4 s. (a) write andrews time in standard notation. (b) evelyn ran a marathon in 4 h and 16 min. who ran the shortest amount of time? show your work.

Step-by-step explanation:

(a) 1.56×10^4 = 1.56×10000 = 15,600

(b) There are 3600 seconds in an hour, so Andrew's time was

  15600 s/(3600 s/h) = 13/3 h = 4 1/3 h

1/3 hour is 20 minutes, so Evelyn's time of 4:16 is shorter than Andrew's time of 4:20.

if x = 1, then the answer is 3.5

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8