As reported by a recent survey, the fast-food restaurant with the best drive-through time had a mean time spent in the drive-through of mean= 64.5 seconds. Assuming drive-through times are normally distributed with 2.8 seconds, complete parts (a) through (d) below. (a) What is the probability that a randomly selected car will get through the drive-through in less than 61.7 seconds?

what does the table look like

percent abundance for cu-63 can be shown as:

63 x + 65 (1-x) = 62.9296

65 - 62.9296 = 2 x

x = 1.035

thus, percent abundance for cu-63 is 1.035

percent abundance for cu-65 can be shown as:

63 x + 65 (1-x) = 64.9278

65 - 64.9278 = 2 x

x = 0.0361

thus, percent abundance for cu-63 is 0.0361

the mass spectrum of cu-63 showing the intense peak as, this isotope is found in nature more abundantly around 92.38 % in comparison to cu-65 which is found 62.58 % naturally