Explanation : x = 79 marks
The marks scored by Mike on four math test are 88,91,75 and 72.
Average of marks, A = 81
Let in fifth test he scores x marks.
The formula for finding average is :




In the fifth test he scores 79 marks.
Hence, this is the required solution.
Answer:
<u>A common element among all the river valley civilizations was irrigation systems that moved water to crops and settlements</u>
Explanation:
- <u>River Valley civilizations where the civilizations that were found on the banks of the river like the Mesopotamia ,Indus valley civilization.</u>
- <u>These civilization where agriculture based civilization as they depended on river for drinking water and irrigational activities</u>
Answer:
B. a food chain
Explanation:
Food chain: a hierarchical series of organisms each dependent on the next as a source of food.
That fact can be explained by the similarity in their genes.
Dogs and coyotes are from the same class, family and genus (Mammalia, Canidae, Canis).
This is almost enough for their offspring to be viable. But if the DNA is similar (which it is) offspring the chances of viable and fertile offspring is high almost at 100%.
Hope it helped,
Happy homework/ study/ exam!
When people don't know how to drive the boat correctly and they loose control.