In general, it is felt that ice ages are caused by a chain reaction of positive feedbacks triggered by periodic changes in the Earth's orbit around the Sun. The last ice age ended about 12,000 years ago. The next cooling cycle would be expected to start about 30,000 years or more into the future.
The two main states of mechanical energy are potential energy and kinetic energy.
A.
The invasive shrimp will begin to overpower the native shrimp population, as predators will not like to eat the invasive species as much.
Answer:
68.57 mile/hour
Explanation:
The distance from Yakima to Ellensburg is 50 miles and you travel with 60 miles/hour for the first 25 miles, then 80 miles/hour for the last 25 miles. The easy way to solve this question is to find the total time needed to travel.
The time needed to travel 25 miles with 60 miles/hour speed will be: 25 miles/ (60 miles/hr)= 0.42 hr
The time needed to travel 25 miles with 80 miles/hour speed will be: 25 miles/ (80 miles/hr)= 0.31 hr
Total time needed to travel 50 miles will be: 0.41 hr + 0.31hr = 0.73 hr
The average speed will be:
average speed= sum of travel distance/ sum of time needed= 50 miles/ 0.73hr= 68.57 mile/hr