Traditions Clothing Store is having a sale. Shirts that were regularly priced at $20 are on sale for $17.what is the percentage of decrease in the price of the shirts? () A. 3% B 15% C 18% D 85%
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18% , and the true value is 80.13%,could you find the absolute error of measurable result? ( )
A. 0.05
B. -0.05
C. 0.05%
D. -0.05%
The electron configuration of element 25 is [] 3d54s2, then it is in () period of periodic table.
A. 2
B. 3
C. 4
D. 5
What is the conjugate acid of HCO3-? ( )
A. CO32-
B. H2CO3
CO2
D. H2O
If the equilibrium constant Kbof C6H5COO–in water is 1.5×10-10, the equilibrium constant Kaof C6H5COOH is ( ).
A. 1.0×10-3
B. 5.0×10-11
C. 6.7×10-5
D. 1.5×10-10