Add 7.3×107+1.8×107 . Which is the correct sum?(1 point)
Responses
8.1×107
8.1 times 10 superscript 7 baseline
9.1×1014
9.1 times 10 superscript 14 baseline
9.1+107
9.1 plus 10 superscript 7 baseline
9.1×107
9.1 times 10 superscript 7 baseline
The population of a city is given as 3.45×106 . A nearby city has a population of 1.3×105 . What is the sum of the populations of the two cities in scientific notation?(1 point)
Responses
35.8+105
35.8 plus 10 superscript 5 baseline
3.58×106
3.58 times 10 superscript 6 baseline
4.75×105
4.75 times 10 superscript 5 baseline
4.75×1011
3.58×106
An empty dump truck weighs about 2.8×105 pounds. How much does it weigh if 15,300 pounds of trash is added? The answer should be in scientific notation.(1 point)
Responses
4.33×105 pounds
4.33 times 10 superscript 5 baseline pounds
29,530 pounds
29,530 pounds
2.953×105 pounds
2.953 times 10 superscript 5 baseline pounds
15,302.8 pounds
2.953×105 pounds
The half-life of uranium-235 is 700,000,000 years. The half-life of uranium-238 is 4.463×1011 years longer. What is the half-life of uranium-238? The answer should be in decimal form.(1 point)
Responses
11,463,000,000
11,463,000,000
516,300,000,000
516,300,000,000
447,000,000,000
447,000,000,000
4.4637×1011
4.4637×1011
A mobile phone holds 1.28×1011 bytes of storage. You can also pay more money to get an additional 384,000,000,000 bytes. How much storage would your phone have if you buy the additional bytes? The answer should be in scientific notation.(1 point)
Responses
385.28×1011
385.28 times 10 superscript 11 baseline
512×109
512 times 10 superscript 9 baseline
385,280,000,000
385,280,000,000
5.12×1011