What does this weather map symbol represent, and what is its meaning?
a. moving front: the area between two air masses where is constantly in motion
b. stationary front: the boundary between two air masses where no air is moving
c. cold front: the leading edge of a cold air mass is pushing against a warm air mass
d. warm front: the leading edge of a warm air mass is pushing in to replace a cold air mass

i believe the answer is true.

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