(4 marks) .. A hydrogen balloon at the Earth's surface has a volume of 5.0m on a day when the
temperature is 27°C and the pressure 1 atm. What is the mass of hydrogen? The balloon
rises and expands as the pressure drops. What would be the volume of the same number
of molecules of hydrogen at an altitude of 40km where the pressure is 0.33X10 Pa and
temperature is -13°C
(8 marks)​

Groups of organs that work together to complete a process in the body are called: a. cells b. tissues c. nerves d. systems

Mass (kg) force (n) 5 25 10 50 15 75 20 100 a student was trying to find the relationship between mass and force. he placed four different masses on a table and pulled them using a spring scale. the table shows the different masses used in the experiment and the force required to pull each mass. the student concluded that more force was required to pull heavier objects. what comment would you make regarding his conclusion? a) no clear relation can be observed between mass and force from the data. b) there is a direct proportion between the mass and force listed in the table. c) gravity should have been taken into account while performing the experiment. d) there is an inverse proportion between the mass and force listed in the table.

An open cart is moving along a straight frictionless horizontal track. when rain starts falling vertically into the cart, what happens to the speed of the cart?