Answer:
The forces acting on the pen which is still on the table can have two forces acting on them. The forces are gravitational force and the equal and opposite force to the gravitational forces.
The equal and opposite forces that is applied on the pen keeps the pen still on the table.
So, the statement that no force is applied on the pen which is kept still on the table is wrong as two forces are applied on the pen.
As both the forces are equal and opposite so it is cancelled and is still.
Answer
The ways are;
• By commercializing low earth orbit
• By supporting water purification efforts worldwide
• By bringing space station ultrasound equipment on earth
• By improving eye surgery with space hardware
Explanation
There is a revolutionary commercial pathways that is currently opening access to space.For example, NASA is purchasing commercial cargo resupply to space station which enable U.S business to develop a competition in selling services to others while freeing NASA resources for deep space exploration. Using technology developed in space, the Water Security Corporation has deployed systems using NASA water-processing technology to ensure drinkable water availability for human survival. Medical care in remote regions is now facilitated by use of small ultrasound units, tele-medicine and remote guided methods similar to those used in space. The Eye Tracking Device experiment has enable researchers to have an insight into corrective laser surgeries.
Answer:
Only (I) is true
i) Mass is conserved during a chemical reaction.