Answer: B. Wave A is louder than Wave B.
Explanation: The loudness of sound is measured in unit called decibels (dB).
A decibel unit measures the relative intensity of sounds on a scale from zero to about 100 dB. dB is a measure of intensity, which relates to how much energy the pressure wave has.
Given : Wave A is rated at 100 dB, and Wave B is rated at 90 dB.
Thus we can infer that as wave A has a higher value than wave B, wave A is more louder than wave B.
The correct option is 3.
Enzymes are biological catalysts which speed up the rate of biochemical reactions inside the cells. Enzymes are very specific in action and they require specific conditions called optimum conditions for them to function optimally.
When the optimum conditions are not met, an enzyme's activity will be lowered or totally stopped.
Conditions that affect the optimum activity of an enzyme include: temperature, pH level and regulatory activity of regulatory enzymes and hormones.
4. When you look up to the sky, it appears as a dark circle with halo light at its edges moving across the face of the sun. As it does, depending on the relative position of the person on earth – that determines where they are on the umbra or penumbra of the eclipse, the place becomes a daytime twilight (umbra) or partial twilight (penumbra).
5. A new moon is formed when the moon is in between the sun and the earth. This is converse to the case of a lunar eclipse where the earth is between the sun and moon. In a new moon, the face of the moon that is faced towards the earth is dark because it is not lit by the sun. It is important to note that a solar eclipse is not formed because the moon’s orbit, around the earth, is tilted at an angle.