In the following question, out of the four alternatives, select the alternative which will improve the bracketed part of the sentence. In case no improvement is needed, select "no improvement".
It must (being) quite an exciting time to be alive.
In the following question, out of the four alternatives, choose the word which is opposite in meaning to the given word and click the button corresponding to it. OBSTINATE
Carbon dioxide (CO2) gas dissolved in water can cause water to become acidic.The acidity of water from dissolved CO2 can be reduced by a base such as baking soda (sodium bicarbonate).