Which of the following elements is not a metalloid?
a. boron
b. sulfur
c. silicon
d. arsenic

Can someone me with 3 and 4 plz. this is for masteries test.

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.

Chromosome 17 is made of over million base pairs.