FITRA

Fitra should be given as food according to majority of scholars. Unfortunately it is not the practice in Indo-Pak subcontinent. There is a difference in opinion to pay off Fitra in "money". But it is also allowed but not preferable.
Fitra calculation: One saa for one individual [even new born baby] in a family. One saa is equal to 4 mudd [one mudd is equal to the amount held by cupping the two hands together by an average built adult] It is measured by volume not by the weight.
Food items allowed for Fitra: [any of the following food]

Dates
Barley
Raisin
Cottage cheese

So money will be variable according to current market value and due to variability in selecting food item.
For example if you select Raisin [kishmish] then it will be higher than Barley, while both are valid. So $5, $6 and $10 are all valid. However, extra money will be considered as Sadaka.
In Canada Nisab for Zakat is $206.45. [calculated on 7th October 2002, price value of 21.605 oz Silver] So if you have money in your hand $207.00 at the end of a complete financial year, you are entitled as an "Al-Nisab Al-Malik". So you have to give zaka. Nisab is the term used to identify a person qualified for giving away Zakat.
Payment: There is nothing with Nisab. Whatever you have in hand in cash and wealth, you have to give Zaka at the rate of 2.5% [this means for every 40 dollar, one dollar is due]
Here is an example of calculating Zaka:

Gold 5.2 bori valued = 42,640 Taka
Silver = 0
Amount in Bank cheking account = 24,000 Taka
Fixed deposit [without interest] = 70,000 Taka
Bond = 7,500 Taka
Share = 5,000 Taka
Total amount is 1,49,140 Taka. [Zakat of 2.5% of this amount is due]

If there is debt about 45,000 Taka [this debt should be for basic livelihood purpose]
So his amount is [149140-45000] = 104,140 Taka 2.5% of these is 2603.50 Taka
Any ornament made of gold or silver is accountable for Zakat. [Stones embedded in an ornament are exempted from Zakat]
Zakat is an economic worship like Salah is physical worship, so for woman who owns ornaments, she has to pay her Zakat by herself. But her husband can pay on her behalf. Otherwise she has to sell her commodity for paying Zakat. There is no excuse of being a housewife. But husband can help. But it is not obligatory to husband to pay off zakat for wife. Punishment will be awarded to wife as an individual.