How many significant figures are in the measurement 0.2050 meters? A. 3
B. 5
C. 2
D. 4

D.4

Explanation: Starting at the left side where the decimal is  (because you start with a non-zero integer) the 2 and 5 are obviously significant. The first 0 is significant because it is between two non-zero integers, and the second is significant because it is at the end of the number (this only counts at the end of a decimal!!).

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons

answer; talc and gypsum;