Answer:
Examples of muscle-strengthening activities include:
lifting weights.
working with resistance bands.
heavy gardening, such as digging and shovelling.
climbing stairs.
hill walking.
cycling.
dance.
push-ups, sit-ups and squats.
Explanation:
Blasts are used for communicating different signals when vessels move.When a boat is leaving, a long blast, at intervals of not more than two minutes, is used for alerting other vessels, when a boat is sailing. When leaving the dock, only a single prolonged blast is used for indicating others, that you are leaving.
Answer:
(1) 0.333 Hz
(2) 4 sec
(3) 2 sec, 0.5 Hz
Explanation:
(1) We have given time period of pendulum is 3 sec
So T = 3 sec
Frequency will be equal to 
(2) Frequency of the pendulum is given f = 0.25 Hz
Time period is equal to 
(3) It is given that a pendulum makes 10 back and forth swings in 20 seconds
So time taken to complete 1 back and forth swings = 
So time period T = 2 sec
Frequency will be equal to 
Answer:
Elements in group IIA have 2 electrons in their outermost shell so they can donate these electrons of group VII A which have seven electrons in their outermost shell. So it is necessary 2 elements of group VII A, each atoms accepts one electron.
Explanation:
