Question 3 of 10 The graph shows the percentages of different types of lightbulbs shipped to
consumers in North America over three years.
Percentages of Lightbulbs Sold Annually
to Residents in North America, by Type
2015
2014
Halogen
Incandescent
Compact fluorescent
(CFL)
Light-emitting diode
(LED)
2013
0% 10% 20% 30% 40% 50% 60% 70%
Fluorescent
The demand for which kind of lightbulb has decreased during this time

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.