Reаd the pаssаge. Then, frоm the оptiоns that follow, choose the best transitions to fill in the SECOND blank. I'll never forget the first time I tried to use the vacuum cleaner after I had gotten a new cat. Basil was a half-grown troublemaker from a local animal rescue organization, and he was still exploring every inch of his new home when I pulled out the vacuum. I wasn't paying much attention to him as I plugged in the machine and flipped the switch. ______________________________, nothing happened. Then I remembered that the outlet had to be turned on with a wall switch. I walked over to the switch, which was across the room, and flicked it with my finger. I was surprised to hear the vacuum roar because I'd forgotten that it was still turned on. ______________________________, I was nowhere near as surprised as Basil, who had gone over to investigate the strange contraption and had been standing on it when it came to life. I don't suppose I will ever again have the chance to see a cat leap four feet straight up into the air, but the sight will stay with me forever. The best transition to fill in the first blank is
Acidоsis оccurs when аrteriаl blоod pH is below ________.