Carlos made a study chart about changes to the environment that are caused by humans.

X
-Results from introducing harmful substances into the environment
-Causes an increase in ultraviolet radiation that reaches Earth

Y
-Results from the rising human population
-Causes the disappearance of many species in a short amount of time

Which headings best complete the chart?

A-X: Ozone Layer Destruction
Y: Mass Extinction

B-X: Long-Term Changes
Y: Short-Term Changes

C-X: Short-Term Changes
Y: Long-Term Changes

D-X: Mass Extinction
Y: Ozone Layer Destruction

The frequency of vibrations of a vibrating violin string is given by f = 1 2l t ρ where l is the length of the string, t is its tension, and ρ is its linear density.† (a) find the rate of change of the frequency with respect to the following. (i) the length (when t and ρ are constant) (ii) the tension (when l and ρ are constant) (iii) the linear density (when l and t are constant) (b) the pitch of a note (how high or low the note sounds) is determined by the frequency f. (the higher the frequency, the higher the pitch.) use the signs of the derivatives in part (a) to determine what happens to the pitch of a note for the following. (i) when the effective length of a string is decreased by placing a finger on the string so a shorter portion of the string vibrates df dl 0 and l is ⇒ f is ⇒ (ii) when the tension is increased by turning a tuning peg df dt 0 and t is ⇒ f is ⇒ (iii) when the linear density is increased by switching to another string df dρ 0 and ρ is ⇒ f is ⇒