Frost occurs when dew freezes. what must have happened the previous night for there to be frost on the ground in the morning? select all that apply.

a. precipitation occurred.
b. the sky was covered with clouds.
c. the relative humidity reached 100 percent.
d. the temperature dropped below 0 °c.
e. there was surface runoff at some point.

The investiture controversy began as a power struggle between pope gregory vii (1072–85) and henry iv, holy roman emperor (1056–1106).[2] a brief but significant struggle over investiture also occurred between henry i of england and pope paschal ii in the years 1103 to 1107, and the issue played a minor role in the struggles between church and state in france, as well.by undercutting the imperial power established by the salian emperors, the controversy led to nearly 50 years of civil war in germany, and the triumph of the great dukes and abbots. imperial power was finally re-established under the hohenstaufen dynasty. historian norman cantor:

Answer (true);

Just do the math, then think