Light glows for every 17 seconds . How many times did it between 1:57:58 and 3:20:47 am	Choices
A) 291	B) 292	C) 293	D) 384	E) 285

Rationale: "the diff in sec between 1 : 57 : 58 and 3 : 20 : 47 is 4969 sec , 4969 / 17 = 292 . so total 293 times light ll glow answer : c"
Answer: C