Yes or No? (Economic growth has slowed down/up...)

Dear Sir,

Please answer only “yes” or “no” (ex: a. Yes (that means the same meaning))

a.Economic growth has slowed/has slowed down/has slowed up a little. The same meaning for 3 cases?
b.The car slowed/slowed down/ slowed up as it approached the junction. The same meaning for 3 cases?
c.The game slowed/slowed up/slowed down a little in the second half. The same meaning for 3 cases?
d.The ice on the roads was slowing us down/was slowing us/was slowing us up . The same meaning for 3 cases?
e. You must slow down/slow up/slow a little. The same meaning for 3 cases?
f. We hope to slow/slow up/slow down the spread of the disease. The same meaning for 3 cases?

thanks
K

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Sorry; I find it very difficult to follow such strict instructions.
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Dear Sir,

Yes, that is very difficult. So, can you tell me if “up” ," down" are the words with meanings or they are only the expletive words.

Thanks
Khanh

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Interesting. Yes, the members of each triplet are synonymous, and up and down are expletives— except for this one:

e. You must slow down/slow up/slow a little.

Slow here with no up or down sounds non-native to me; I don’t know why.

(PS: I am actually not sure that these adverbs are expletives; although they carry no specific extra meaning, they do emphasize the movement of deceleration.)
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Thanks Sir,

That’s what I need.

Take care.
Khanh