What is the most probable cause of weak suction in a vacuum cleaner if the hose, the bag, and the filter are not clogged

What is the top speed in a parking lot? a. 10 mph b. 20 mph c. 25 mph d. 30 mph

Which of the following is not permitted in a roundabout? a. using your turn signal b. following the rules of right-of-way c. driving at the speed limit d. changing lanes

This is science by the way which of the following is an example of an environmental pressure a. the air pressure in the atmosphere b. a lake that is gradually running out of water c. a fight between two members of the same species d. breeding between two members of the same species