Lyndon is investigating whether putting plastic on her windows will seal out cold winter drafts. she covers a window on the south side of her house with plastic and measures the inside temperature near the window. she also measures the inside temperature near a window without plastic on the north side of her house. the windows are the same size and design. why is this not an ideal controlled investigation?
a. the windows should be different sizes to introduce variation.
b. the drafts at each window may be different because the windows aren’t near each other.
c. temperature isn’t a good indicator of cold winter drafts.
d. outside temperature is a better indicator of cold winter drafts than inside temperature.
e. the type of plastic used in the investigation isn’t mentioned.

the answer is b. the drafts at each window  may be different because the windows aren't near each other

Answer is: B.The drafts at each window may be different because the windows aren’t near each other.

The two main variables in an experiment are the independent and dependent variable.

Dependent variable (in this example temperature) is the variable being tested and measured in a scientific experiment.

Dependent variables depend on the values of independent variables (in this example the draft). The dependent variables represent the output or outcome whose variation is being studied.

sry but any answer choices

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

neutral atoms of elements after calcium contain d electrons. the energy of d orbitals of a particular main shell lies between the energy of the s and p orbitals of the next main shell. for example, electrons in the have energy higher than those in the orbital while lower than those of the orbital.

by the aufbau principle, electrons fill orbitals one at a time, starting from those of the lowest energy. the orbital is therefore filled right after orbitals and before orbitals.  

potassium has electron configuration and calcium . the s orbital of a main shell holds a maximum of two electrons. the next element would thus have the electron configuration and satisfy the requirements.

a neutral atom of the element contains three electrons on top of the most recent noble gas element. it should thus be placed in the third column of the periodic table. both scandium and yttrium would satisfy the conditions. an aufbau diagram indicates that the 4f orbital is filled before the 5d. however, it appears that exceptions exists for both lanthanum and actinium. neutral atoms of the two d-block elements also demonstrate the and should be highlighted as well.