The substance used to attract the gypsy moth is

The red algae are able to grow at greater depths in the sea than any other photosynthetic organism. What could be the reason/s?
1. The chlorophyll found in red algae is very efficient in absorbing all forms of light making it possible for them to photosynthesize at such depths
2. Their chloroplast structure is such that it makes them absorb the dimmest light available at such depths
3. The phycobilin pigments that they share with bluegreen algae efficiently absorb the green, blue, and violet light that penetrates great depths Which of the above is/are the correct reason/s?

Consider the following:
1. Cylinder
2. Spark Plug
3. Piston
Which of the above is / are used in Diesel engine?

Ultrasounds are used extensively in industries and for medical purposes. Which among the following is / are applications of Ultrasound?
1. Detect cracks and flaws in metal blocks
2. Echocardiography
3. Treatment of Kidney stones
4. Cleaning of odd shaped objects
Select the correct option from the codes given below:

Guard bands increase the bandwidth for

For separate channels in TDM, it is necessary to use

When useful bandwidth of medium exceeds the required bandwidth of signals to be transmitted we use

Which multiplexing technique is used to transmit digital signals ?

Which one of the following is one of the primary producers ?

The most abundant element in sea water is