If a scientist wants to design an experiment to measure the effect of vitamin c on colds, which of the following would be an appropriate placebo?
a. half the recommended daily amount of vitamin c
b. a sugar pill that does not contain vitamin c
c. the recommended daily amount of vitamin d
d. the recommended daily amount of vitamin c

b.  A sugar pill that does not contain Vitamin C

Explanation:  

It has to be a sugar pill because a placebo (or dummy pill) is an inert (inactive) substance, typically a tablet, capsule or other dose form that does not contain an active drug ingredient.

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.