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Atrain travels 74 kilometers in 3 hours, and then 81 kilometers in 5 hours. what is its average speed?

What rule is used to determine how many covalent bonds an element can form? a. the number of covalent bonds is equal to six c the number of covalent bonds is equal to five minus the group number plus the group number b. the number of covalent bonds is equal to eight d. none of the above minus the group number select the best answer from the choices provided

Rays from the sun are not considered matter true or false