PLEASE HELP I DONT UNDERSTAND AT A

If the temperature of 153.7 L of a gas at 38.6 ºC falls by 9.6 Cº, what is the new volume of the gas if the pressure is constant?
Select one:
a. 149
b. 153.700
c. 115
d. 139.40

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

Animals that reproduce sexually either do it through external or internal fertilization. read the following statement and decide if it is true or false. birds reproduce through external reproduction which is because the female will then be able to protect the egg.